Osbourne, 61, showed her loyalty when she swung by the venue to support ousted X Factor reject Shelley Smith perform.

Little did she know Gaga – who she has dubbed ‘a publicity-seeking hypocrite’ – had decided on a last-minute impromptu performance of her new single Venus, which saw her strip completely bare in front of thousands of stunned fans.

‘Sharon is so loyal. She swung by to see Shelley,’ said my club source. ‘Gaga then literally decided last-minute that she would come down to the club and perform.

‘Both she and Sharon then shared the same backstage area,’ said the insider, who was spared being witness to a catfight.

Instead the source revealed: ‘Sharon and Gaga spent time together backstage. They sat talking for a while.

‘They were happy to share the space before having a private conversation. They are both amazing women and both about “love” at the end of the day. There were no hard feelings.’

The impromptu peace pact left X Factor bosses breathing a sigh of relief last night, as they were expecting fireworks from outspoken Mrs O over Gaga’s performance on the talent show.

The pair’s bitter feud dated back to when Osbourne’s daughter, Kelly, had suggested Gaga was covering up a pregnancy at the 2012 Grammys.

Gaga, 27, accused the 28-year-old Fashion Police host of encouraging bullying and said her job on the show was ‘rooted in criticism’, before Osbourne junior hit back, claiming she’d been bullied by the singer’s Little Monster fans online.

That’s when Mrs O waded in with an open letter savaging the Applause singer and accusing her of double standards.

Meanwhile, after peace broke out, fans were left gobsmacked by Gaga’s ‘phenomenal’ performance at the club.

After stepping off stage, Gaga tweeted: ‘Had an amazing night tonight at G-A-Y in London. After all these years you continue to inspire me. Can’t wait for X-Factor tomorrow night! (sic)’